OK, OK, so maybe I'm overstating my circumstances somewhat. Samantha Cameron hasn't asked me round to her and Dave's Notting Hill pad for an informal supper of organic hotpot, or anything. When I say 'party', I actually mean 'press launch for Smythson', the purveyors of ruinously expensively, covetable jewel-coloured leather frippery and stationery; a company of which Samantha is creative director. And when I say 'Samantha Cameron's invited me ...' I actually mean 'some PR person popped me on a guest list for frankly God knows what reason.' But none the less - I will shortly be standing in the actual physical presence of Samantha Cameron, who will possibly be obliged to smile at me in the name of nurturing good press relations; and whose essence, most significantly, I will then try to absorb via osmosis.

I want to be Samantha Cameron. Or at least, I think I should want to be Samantha Cameron. We're the same age, Sam Cam and me; we're both 35. And yet Sam Cam is the epitome of what I am not. She is a grown-up lady. I am a feckless faux-girlie type on the run from maturity. She is married with three children. I am inclined to turn down all reasonable proposals of marriage because I think I'm too interesting for that; ditto breeding. Sam Cam copes wonderfully, effortlessly moving between her role as a mother and nurturer of a disabled child and high profile Tory wife, to consummate Bond Street-based professional person. I cope with very little: I cry, all the time, often just because someone's ended a phone conversation with me a little too brusquely. Getting dressed every morning sometimes seems like an overwhelmingly challenge (I still insist on wearing clothes made for girls half my age).

When Sam Cam has a dinner party, I imagine it's all sixty quid pies from the posh West London butchers Lidgates, bonnes mots and biting insight, culminating with a reasonable, mildly tipsy bedtime for everyone concerned.

When I go to a dinner party (I never throw them - can't cook, don't care), it starts off well enough, but ends with a riot of drunkenness, a disco in the kitchen, and a finale during which my friend Julie Goose takes her top off. (She thinks it's a sign of maturity that she now keeps her bra on in such circumstances. I do, too.) You get the idea. The only thing Sam Cam and I have in common, apart from the year of our birth, is a fondness for Topshop coats, and medium brown hair.

Every decade has its Sam Cam. A serene, orderly, cashmere-swaddled type of a woman; a proper lady, whose main function is to make all other women of her age feel totally inferior, messy and like they really should get a grip and grow up. Now, please. In the Nineties, we had Nigella Lawson. In the Eighties, we had ... actually, I've got no idea who we had, I was too busy fixating on George Michael to bother with such matters; but there would definitely have been someone to inspire a bittersweet combination of crushy-type passion, seething envy, and a rampant sense of inferiority in the thirtysomethings of the age. And now we've got Sam Cam who, it seems, I am on the brink of stalking in my efforts to get my head round my impending middle age.

Although actually, I suspect that my lady crush on Sam Cam will be short-lived. I've known I should grow up and get on with life for 18 months or so now, and I've done nothing about it before she came onto the scene. Furthermore, I remember how wildly we all loved Nigella Lawson back in 1999, how passionately we aspired toward the giddy heights of Domestic Goddess-hood; and then how rapidly we got bored (with both Lawson's celebrity persona and also the laborious preparation of mushroom risottos) and didn't any more.

Furthermore, and probably most significantly, I am no kind of a Tory - let alone a Tory wife; which is something I'll try to remember come general election time. I'm prepared to sacrifice life as a fully functioning adult in the name of making that sort of political statement. Yes I am.

And anyway, a small part of me already knows that what I'd really, really like, is not Sam Cam's perspective or maturity - but rather her unfettered access to all that lovely, lovely Smythson.